One vertex per element, one color per generator, with an edge from x to x·s.
(2,3)(5,6)(7,9)(8,10)(11,12)(15,22)(19,27)(23,28)(24,25) involution — undirected(1,2,4,3)(5,7)(6,9)(8,11)(10,12)(13,14)(15,23)(16,20)(17,26)(18,21)(19,25)(22,28)(24,27)(6,10)(7,11)(15,22)(19,27)(23,28)(24,25) involution — undirected(6,10)(9,12)(13,15,16,24,18,22,17,25)(14,19,26,28,21,27,20,23)(1,3,4,2)(13,16,18,17)(14,20,21,26)(15,24,22,25)(19,23,27,28)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.